BT Boosted by Broadband Investment

U.K. telecommunications operator BT Group PLC Friday marked an end to 4½ years of declining revenue, as billions of pounds spent on new cables for superfast fiber broadband started to pay off.

The U.K. is undergoing a sea-change in the telecom and media industry as the lines become blurred between telecom, Internet and television. BT, the former telecom monopoly, has suffered from dwindling demand for its fixed line phone services and...